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EQUIPMENT CABLING CHAPTER 9: EQUIPMENT INSTALLATION<br />

9.9.3 CABLING REQUIREMENTS FOR CABLE TRAYS OR LADDERS<br />

9.9.3.1 CABLE INSTALLATION WITHIN CABLE TRAYS OR LADDERS<br />

• Cables that span a horizontal gap greater than 610 mm (2 ft.) shall be supported.<br />

• When installing cables into a cable tray system, cables shall not be pulled with such <strong>for</strong>ce that the<br />

conductor insulation or cable jacket integrity is destroyed or that the cable is de<strong>for</strong>med.<br />

• Antenna <strong>and</strong> transmission lines minimum bending radii shall be considered when placing these<br />

cables within the cable tray. Follow manufacturers’ specifications.<br />

• Cables installed within a cable tray system shall be fastened securely to transverse members in all<br />

horizontal <strong>and</strong> vertical runs every 914 mm (36 in.).<br />

• The most desirable method to exit the cable runway is to drop out the bottom into a rack/cabinet or<br />

a vertical support such that physical separation is maintained.<br />

• AC power cables shall not be run within a cable runway system unless they are enclosed within<br />

metallic conduit or raceway.<br />

NOTE: Raceways or conduit installed below or along side cable runways may not be supported by the cable<br />

runways themselves unless the cable runway system is designed to provide such support.<br />

9.9.3.2 CABLE SEPARATION AND GROUPING WITHIN CABLE TRAYS<br />

• Cable groups shall be separated a minimum of 50.8 mm (2 in.) from other cable groups. (See<br />

ANSI/TIA/EIA-568(b) <strong>and</strong> 569(b); NFPA 70-2005, Articles 800-133, 800-18, <strong>and</strong> 820-133 <strong>for</strong><br />

additional in<strong>for</strong>mation.)<br />

• Transmission lines (coax) <strong>for</strong> transmitting stations shall be separated a minimum of 101 mm (4 in.)<br />

from electrical lights, power, <strong>and</strong> signaling circuits (NFPA 70-2005, Article 810.70).<br />

• Groups are defined as:<br />

• AC power, DC Power, ground conductor <strong>and</strong> RF transmission cabling<br />

• Data, control, signal <strong>and</strong> timing reference cabling<br />

• Telephone cabling<br />

• At a minimum the above group separation must be maintained. However with adequate cable tray<br />

space, logical sub-groups are permitted such as, bundles of DC cabling, bundles of RF cabling, etc.<br />

• AC power cables cannot be run in the same cable tray as CAT-5 or <strong>communication</strong>s cables unless<br />

separated by a barrier as defined by NFPA 70-2005. (See “Computer Network Cabling” on<br />

page 9-18 <strong>for</strong> additional in<strong>for</strong>mation.)<br />

9-14 68P81089E50-B 9/1/05

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